The Brazilian Militia is an enemy faction in Call of Duty: Modern Warfare 2. They reside in Rio De Janeiro where they come into conflict with Task Force 141. They are also a playable multiplayer faction. Their faction symbol is a blood-red handprint. Rather than a real, official militia, they are little more than a criminal gang, but they are a very large and well-armed one, sporting a colorful mix of civilian garb and military hardware. They appear in the two campaign missions Takedown, and The Hornet's Nest as well as the three special ops missions: Bomb Squad, Alpha, and O Cristo Redentor.

Unlike common gangs, the Militia is very well armed and numbers in the hundreds. It is likely that they comprise the entire gangster population of Rio. Though not the most efficient soldiers, they are sufficiently well-equipped and well-led to prove a very serious threat to Task Force 141, using their numbers and hardware to put up a heavy fight. Speculation is that Alejandro Rojas, their main supplier, struck a deal of some sort with them, since they protected him when he was hunted down by the Task Force 141, or they may have thought that Task Force 141 is there for the simple mission of killing them.

Some mistake them to be allied with Vladimir Makarov and the RussianUltranationalists, although that is not possible. Their only connection to them is through Rojas, who supplied Makarov the weapons for the terrorist attack in Russia. They use weapons built locally in Brazil, and Russian weaponry such as the AK-47. They also use attack dogs. In battle, they are deceptively formidable tacticians, and will frequently attempt to ambush or flank the player. However, they are a lot more foolish on easier difficulties, blind firing frequently and running straight through fire to their deaths.

When the character is about to throw a flashbang he yells: "Apareceu de repente!" (Appeared all of a sudden!) or "atirando uma granada de mão" (Throwing a hand grenade). However, when he throws a fragmentation grenade he says Atirando Uma Granada de luz! (Throwing a flash grenade or flashbang).

When the character is about to plant a claymore he yells: "golpeando com Espada!" (Striking with a sword!). Presumably, the translators confused the claymore mine with the Claymore sword.

When the character is about to reload he yells: "trocando de arma!" (changing weapon).

Portuguese speakers within the game, including the militia, have Spanish accents.

In multiplayer, shown in the first person, the militia is wearing combat gloves. However, if viewed in the third person, they do not. The BradyGames strategy guide contains some pre-release images of the militia with gloveless first person hands.

The Riot Shield and sniper models for the Militia both sport some form of Blue Camouflage.

The emblem of the faction can be unlocked in multiplayer by earning the "Streaker" challenge, which is getting 10 kills without dying. This can also be done in Modern Warfare 3.